Self-expandable bag



Nov. 13, 1962 G. D. BLACK 3,063,620

SELF-EXPANDABLE BAG Filed Jan. 6, 1960 2 Sheets-Sheet 1 lnvenlor M L/$ MNov. 13, 1962 G. D. BLACK SELF-EXPANDABLE BAG 2 Sheets-Sheet 2 FiledJan. 6, 1960 United States Patent 3,663,620 SELF-EXPANDABLE BAG GeoffreyDonald Black, Sawbridgeworth, England, as-

signor to The British Oxygen Company Limited, a company of Great BritainFiled Jan. 6, 1966, Ser. No. 747 Claims priority, application GreatBritain Jan. 6, 1959.

1 ZJlaim. {Cl.23043) This invention relates to self-expandable bags foruse in administering inhalant gas. Such bags are intended primarily foruse in the application of intermittent positive pressure resuscitation.

Self-expandable bags are known having a valved inlet through which airor other gas may enter the bag, and a valved outlet for connection to aface mask or the like, so that when the bag is compressed by theoperator, the contents are forced into the lungs of the patient and whenthe pressure is released the bag expands to draw in a fresh supply ofgas Whilst the patient exhales to atmosphere. The valve in the outletfunctions both as a non-return valve and an exhalation valve, beingarranged to permit gas to flow only from the bag to the lungs duringinhalation and from the lungs to atmosphere during exhalation.

The advantage of the self-expandable bag is that it enables the bag andmask method of artificial respiration commonly practised in theoperating theatre to be used under emergency conditions away from thetheatre, for example at the scene of an accident, or during transport ofa patient.

Self-expanding bags as proposed heretofore, even when in the collapsedcondition, are relatively bulky due to the space occupied by the meansprovided for expanding the bag. Such means may, for example, comprisesprings or foam rubber or plastic.

It is an object of the present invention to provide a self-expandablebag for use in administering inhalant gas, which may readily becollapsed when not in use so as to occupy a minimum of space duringstorage.

According to the present invention there is provided a self-expandablebag for use in administering inhalant gas comprising a substantially gasimpervious envelope with at least one opening and at least one tubularinflatable element associated with the envelope to form an integral partof the bag, the element when inflated causing the bag, aftercompression, to assume the expanded state.

According to a feature of the invention a single infiatable element inthe form of a tubular channel extends around the circumference of thebag along a substantially helical or zig-zag path, the channel having aconnection for fluid under pressure.

According to another feature of the invention the inflatable elementscomprise a system of intercommunicating tubular channels extendingaround the circumference of the bag, said channels having a connectionfor fluid under pressure.

The channels may be either secured to or formed integrally with the wallof the envelope. They may be unobstructed tubes or they may be filledwith interconnected cell sponge rubber or plastic. The latter form mayhave the advantage that the walls of the channels cannot seal themselvestogether during prolonged storage.

According to a further feature of the invention the envelope is adouble-walied structure, the walls being united at a plurality of pointsin spaced relationship, and

a connection for fluid under pressure leading to the interspace.

Fluid, for example air, may be introduced into the connection by blowingwith the mouth or by means of a syringe or pump. The connection may beprovided 3,063,620 Patented Nov. 13, 1962 with a displaceable non-returnvalve to enable pressurising fluid to be released at will from thechannels or the interspace.

For use in administering gas the bag has an inlet provided with anon-return valve through which gas may enter the envelope and an outletprovided with a nonreturn valve through which gas may be expelled fromthe envelope. The non-return valve in the outlet preferably functionsalso as an expiratory valve. H

The inlet and outlet may have a common connection to the mouth of thebag but are more conveniently located at opposite ends of the bag. Theenvelope may be made, for example, from rubber or rubberized fabric.

If desired a second inlet to the bag may be provided for connection to asupply of oxygen or other gas.

The invention will now be described by way of example with reference tothe ,drawings in which I FIGS. 1, 2, 3 and 6 are side elevations ofalternative forms of bags constructed in accordance with the invention,

. FIG. 4 is a section taken along the line AA of FIG.

FIG. 5 is a section taken along the line AA of FIG. 3 showing analternative form of internal construction,

FIG. 7 is a section taken along the line B-B of FIG. 6, and

FIG. 8 illustrates diagrammatically an inspiratory/ expiratory valvesuitable for location in the, outlet of any of the bags shown in FIGS.1, 2, 3 and 6.

The embodiment illustrated in FIG. 1 shows an ovoid rubber bagcomprising an envelope 10 having an inlet 11 at one end and an outlet 12at the other end. An.

inflatable element consisting of a rubber tube 13 is bonded to the wallof the envelope and extends in a helical path over its circumference.The tube 1.3 is adapted to be, inflated either ovally or from a suitablesource of fluid under pressure through a connection 14 provided with aplug 15. Instead of the plug 15 a displaceable nonreturn valve may belocated in the connection 14.

A second gas inlet 16 to the interior of the bag is adapted forconnection to a supply of oxygen or other gas. The bag may be made by aconventional rubber dipping process. For example, the envelope 10 may beproduced by dipping a former in rubber latex solution. The tube 13 iswound around the envelope and the whole assembly is then cured wherebythe tube becomes bonded to the wall of the envelope.

When the bag is to be used for administering gas, the inlet 11 is fittedwith a non-return valve through which air may be drawn into theenvelope, and the outlet 12 is fitted with a non-return valve whichfunctions also as an expiratory valve. A suitable valve, which isillustrated in FIG. 8, consists of a tubular member 17, intended forconnection to a face piece for the patient, having a port 18 closed by aflap valve member 19 through which gas is admitted from a passage 20communicating with the interior of the envelope 10, and another port 21closed by a flap valve member 22 through which exhaled gases arepermitted to escape into a chamber 23 provided with vents 24 toatmosphere. The chamber 23 is divided by a diaphragm 25, one side of thediaphragm being subjected to atmospheric pressure through the vents 24,and the other side to a pressure equal to the pressure in passage 20acting through a duct 26 which connects the passage 20 to the chamber23.

In use, the tubular member 13 is inflated, thus causing the bag toexpand and draw in air through the valved inlet 11. Oxygen-enrichment ofthe air is provided by connecting the second gas inlet 16 to a supply ofoxygen. When the bag is squeezed, air is forced through the passage 20and past the valve member 19 into the patients lungs. At the same timethe diaphragm is deflected inwards to bearagainst the valve member 22and maintain it in sealing engagement with the port 21. When pressure onthe bag is released, it expands under the influence of the inflated tube13 to draw in a fresh supply of air. The pressure acting on thediaphragm 25 is simultaneously relieved, the diaphragm moves outwards,and the valve 22 opens to permit the exhaled gases to escape via theport 21 and vents 24 to atmosphere.

The bag illustrated in FIG. 2, which shows a different arrangement ofthe inflatable element, consists of a flexible rubber envelope 27 havingan inlet 28 and an outlet 29, a tube 30 extending in a 'Zig-zag pathover its circumference and adapted to be inflated through a connection31.

Another alternative form of bag is illustrated in FIG. 3 and consists ofa flexible rubber envelope 32 having an inlet 33 at one end and anoutlet 34 at the other end and a system of interconnected tubularchannels 35 adapted to be inflated through a connection 36. A second gasinlet 37 is provided for admission of oxygen or other gas. The channelsare so arranged that when they are inflated, the medialportion of thebag exerts the least resistance to compression. When the bag is squeezedthe tendency to bulge at each end is thus reduced and the maximum volumeof gas can be expelled. The tubular channels 35 may be unobstructedtubes as shown in FIG. 4, or they may be tilled with interconnected cellsponge rubber or plastic 38 as shown in FIG. 5. This form of bag may bemanufactured by dipping a former in rubber latex solution, applying askeleton of metal former tubes to the envelope so produced, andiedipping. The whole assembly is then partially cured before the metaltubes are withdrawn. If the tubular channels are to be filled withsponge rubber, a skeleton of sponge rubber tubes replaces the metalformer tubes during manufacture.

7 Referring to FIGS. 6 and 7, another form of bag is illustrated whichis constructed from two sheets 39 and 40 of substantially gas imperviousmaterial sealed together at each end around an inlet 41 and outlet 42and also sealed together at a plurality of points 43 in spacedrelationship. -An inflating connection 44 leads into the interspace 45between the two sheets.

After use, pressure in the inflatable elements, constituted by thechannels 13, 30, 35 and the interspace 40 respectively, is released tocollapse the bag for packing.

In the collapsed state any of the bags illustrated may be utilised foroxygen therapy, the patient on spontaneous breathing drawing in airenriched with oxygen, or if the oxygen flow is increased to keep the baginflated, pure oxygen.

I claim:

A self-expandable bag 'for use in administering inhalant gas comprisinga substantially gas impervious envelope including an inlet and anoutlet, at least one tubular inflatable element extending around theexternal circumference of the envelope to form a unitary integral partof the bag, said element being filled with interconnected cell cellularmaterial, said element when inflated causing the bag to assume anexpanded state, said inlet in said bag adapted to admit inhalant gasthereto and said outlet adapted to discharge said inhalant gastherefrom, said inlet and said outlet each provided with a nonreturnvalve and said self-expandable bag having a second inlet for connectionto a source of another inhalant gas.

References Cited in the file of this patent UNITED STATES PATENTS2,280,9 0 Alexander Apr. 21, 1942 2,834,339 Bennett May 13, 19583,009,459 Ruben Nov. 21, 1961 FOREIGN PATENTS 923,570 Germany Feb. 17,1955 OTHER REFERENCES German application Ser. No. P 13321, printed April26, 1956 (K1. 27a

